Search Results (156)

Alpha therapy (TAT) relies on combining alpha-emitting radionuclides with specific cell-targeting vectors to deliver a high payload of cytotoxic radiation capable of destroying tumor tissues. TAT efficacy comes from the tissue selectivity of the targeting vector, the high linear energy transfer (LET) of the radionuclide, and the short range of alpha particles in tissues. Recent research studies have been directed to evaluate TAT on a preclinical and clinical scale, including evaluating damage to tumor tissues with minimal toxic radiation effects on surrounding healthy tissues. This review highlights the use of Actinium-225/Bismuth-213 radionuclides as promising candidates for TAT. Herein, we begin with a discussion on the production and supply of [²²⁵Ac]Ac/[²¹³Bi]Bi followed by the formulation of [²²⁵Ac]Ac/[²¹³Bi]Bi-radiopharmaceuticals using different radiolabeling techniques. Finally, we have summarized the preclinical and clinical evaluation of these potential radiotheranostic agents. Full article

Antibody–drug conjugates (ADCs) have revolutionized breast cancer (BC) therapy by combining targeted antibody specificity with potent cytotoxic payloads, thereby enhancing efficacy while minimizing systemic toxicity. This review highlights significant innovations driving ADC development alongside persistent challenges. Recent advancements include novel antibody–drug conjugate (ADC) designs targeting diverse antigens, such as HER2, HER3, and CD276, demonstrating potent anti-tumor activity and improved strategies for drug delivery. For instance, dual-payload ADCs and those leveraging extracellular vesicles offer new dimensions in precision oncology. The integration of ADCs into sequential therapy, such as sacituzumab govitecan with TOP1/PARP inhibitors, further underscores their synergistic potential. Despite these innovations, critical challenges remain, including tumor heterogeneity and acquired drug resistance, which often involve complex molecular alterations. Moreover, optimizing ADC components, including linker chemistry and payload characteristics, is essential for ensuring stability and minimizing off-target toxicity. The burgeoning role of artificial intelligence and machine learning is pivotal in accelerating the design of ADCs, target identification, and personalized patient stratification. This review aims to comprehensively explore the cutting-edge innovations and inherent challenges in ADC development for BC, providing a holistic perspective on their current impact and future trajectory. Full article

Antibody–drug conjugates (ADCs) are a rapidly advancing class of targeted cancer therapeutics that couple the antigen specificity of monoclonal antibodies (mAbs) with the potent cytotoxicity of small-molecule drugs. In their core design, a tumor-targeting antibody is covalently linked to a cytotoxic payload via a chemical linker, enabling the selective delivery of highly potent agents to malignant cells while sparing normal tissues, thereby improving the therapeutic index. Humanized and fully human immunoglobulin G1(IgG1) antibodies are the most common ADC backbones due to their stability in systemic circulation, robust Fcγ receptor engagement for immune effector functions, and reduced immunogenicity. Antibody selection requires balancing tumor specificity, internalization rate, and binding affinity to avoid barriers to tissue penetration, such as the binding-site barrier effect, while emerging designs exploit tumor-specific antigen variants or unique post-translational modifications to further enhance selectivity. Advances in antibody engineering, linker chemistry, and payload innovation have reinforced the clinical success of ADCs, with more than a dozen agents FDA approved for hematologic malignancies and solid tumors and over 200 in active clinical trials. This review critically examines established and emerging conjugation strategies, including lysine- and cysteine-based chemistries, enzymatic tagging, glycan remodeling, non-canonical amino acid incorporation, and affinity peptide-mediated methods, and discusses how conjugation site, drug-to-antibody ratio (DAR) control, and linker stability influence pharmacokinetics, efficacy, and safety. Innovations in site-specific conjugation have improved ADC homogeneity, stability, and clinical predictability, though challenges in large-scale manufacturing and regulatory harmonization remain. Furthermore, novel ADC architectures such as bispecific ADCs, conditionally active (probody) ADCs, immune-stimulating ADCs, protein-degrader ADCs, and dual-payload designs are being developed to address tumor heterogeneity, drug resistance, and off-target toxicity. By integrating mechanistic insights, preclinical and clinical data, and recent technological advances, this work highlights current progress and future directions for next-generation ADCs aimed at achieving superior efficacy, safety, and patient outcomes, especially in treating refractory cancers. Full article

Background/Objectives: Antibody–drug conjugates are a rapidly evolving class of cancer therapeutics that combine the specificity of monoclonal antibodies with the potency of cytotoxic drugs. This review explores experimental and computational advances in ADC design, focusing on structural elements and optimization strategies. Methods: We examined recent developments in the mechanisms of action, antibody engineering, linker chemistries, and payload selection. Emphasis was placed on experimental strategies and computational tools, including molecular modeling and AI-driven structure prediction. Results: ADCs function through both internalization-dependent and -independent mechanisms, enabling targeted drug delivery and bystander effects. The therapeutic efficacy of ADCs depends on key factors: antigen specificity, linker stability, and payload potency. Linkers are categorized as cleavable or non-cleavable, each with distinct advantages. Payloads—mainly tubulin inhibitors and DNA-damaging agents—require extreme potency to be effective. Computational methods have become essential for antibody modeling, developability assessment, and in silico optimization of ADC components, accelerating candidate selection and reducing experimental labor. Conclusions: The integration of experimental and in silico approaches enhances ADC design by improving selectivity, stability, and efficacy. These strategies are critical for advancing next-generation ADCs with broader applicability and improved therapeutic indices. Full article

Gastric cancer (GC) remains a major cause of cancer-related mortality worldwide, with human epidermal growth factor receptor 2 (HER2)-positive disease representing a clinically relevant subset. Trastuzumab combined with chemotherapy is the standard first-line treatment in advanced settings, following the landmark ToGA trial. However, resistance to trastuzumab has emerged as a significant limitation, prompting the need for more effective second-line therapies. Trastuzumab deruxtecan, a novel antibody–drug conjugate (ADC) composed of trastuzumab linked to a cytotoxic payload, has demonstrated promising efficacy in trastuzumab-refractory, HER2-positive GC, including cases with heterogeneous HER2 expression. Other HER2-targeted ADCs are also under investigation as potential alternatives. In addition, strategies to overcome resistance include HER2-specific immune-based therapies, such as peptide vaccines and chimeric antigen receptor T cell therapies, as well as antibodies targeting distinct HER2 domains or downstream signaling pathways like PI3K/AKT. These emerging approaches aim to improve efficacy in both HER2-high and HER2-low GC. As HER2-targeted treatments evolve, addressing resistance mechanisms and optimizing therapy for broader patient populations is critical. This review discusses current and emerging HER2-directed strategies in GC, focusing on trastuzumab deruxtecan and beyond, and outlines future directions to improve outcomes for patients with HER2-positive GC across all clinical settings. Full article

Relapsed/refractory diffuse large B-cell lymphoma and other non-Hodgkin lymphomas represent significant clinical challenges, particularly in patients who have exhausted standard immunochemotherapy and cellular therapies. Bispecific antibodies and antibody–drug conjugates have emerged as promising treatments, offering targeted and more effective treatment options compared to current standards. Bispecific antibodies, including epcoritamab and glofitamab, third-line therapies for diffuse large B-cell lymphoma, are recombinant immunoglobulins engineered to recognize two distinct antigens or epitopes simultaneously. This capability enhances therapeutic precision by bridging immune effector cells and tumor cells and modulating multiple signaling pathways involved in the pathogenesis of non-Hodgkin lymphoma. In the context of new therapies, antibody–drug conjugates, such as loncastuximab tesirine, are therapies composed of monoclonal antibodies linked to cytotoxic agents, in which the antibody selectively binds to tumor-associated antigens, delivering the cytotoxic payload directly to cancer cells while minimizing off-target effects. They combine the specificity of antibodies with the potency of chemotherapy, offering enhanced efficacy and safety in hematological malignancies. Ongoing clinical trials are investigating other molecules like odronextamab and the use of bispecific antibodies in combination regimens and earlier lines of therapy. The aim of this review is to explore actual therapies in relapsed/refractory diffuse large B-cell lymphoma, focusing on bispecific antibodies and antibody–drug conjugates. Full article

Background: Metastatic prostate cancer (mPrC), with a median survival of under 2 years, represents an important unmet medical need which may benefit from the development of more effective targeted drug delivery systems. Several cell surface receptors have been identified as candidates for targeted drug delivery to mPrC cells; however, these receptors were selected for their overabundance on PrC cells rather than for their suitability for targeted delivery and uptake of cytotoxic drug payloads. Methods: We describe a novel, unbiased strategy to isolate peptides that fulfill functional criteria required for effective intracellular drug delivery and the specific cytotoxicity of PrC cells without prior knowledge of the targeted receptor. Phage clones displaying 7-mer cyclic peptides were negatively selected in vivo and then positively biopanned through a series of parent and drug-resistant mPrC cells. Peptides from the internalized clones were then subjected to a panel of biochemical and functional tests that led to the selection of several peptide candidates. Results: The selected peptides do not bind PSMA. Peptide-drug conjugates (PDCs) incorporating one of the peptides selectively killed wild-type and drug-resistant PrC cell lines and patient PrC cells but not normal prostate tissue cells in vitro. The PDC also halted the growth of PC3 tumors in a xenograft model. Conclusions: Our study demonstrates that adding unbiased, functional criteria into drug carrier selection protocols can lead to the discovery of novel peptides with appropriate properties required for effective targeted drug delivery into target cancer cells. Full article

This study aimed to design dual-responsive chitosan–polylactic acid nanosystems (PLA@CS NPs) for controlled and targeted ledipasvir (LED) delivery to HepG2 liver cancer cells, thereby reducing the systemic toxicity and improving the therapeutic selectivity. Two formulations were developed utilizing ionotropic gelation and w/o/w emulsion techniques: LED@CS NPs with a size of 143 nm, a zeta potential of +43.5 mV, and a loading capacity of 44.1%, and LED-PLA@CS NPs measuring 394 nm, with a zeta potential of +33.3 mV and a loading capacity of 89.3%, with the latter demonstrating significant drug payload capacity. Since most drugs work through interaction with DNA, the in vitro affinity of DNA to LED and its encapsulated forms was assessed using stopped-flow and other approaches. They bind through multi-modal electrostatic and intercalative modes via two reversible processes: a fast complexation followed by a slow isomerization. The overall binding activation parameters for LED (cordination affinity, K_a = 128.4 M⁻¹, K_d = 7.8 × 10⁻³ M, ΔG = −12.02 kJ mol⁻¹), LED@CS NPs (K_a = 2131 M⁻¹, K_d = 0.47 × 10⁻³ M, ΔG = −18.98 kJ mol⁻¹) and LED-PLA@CS NPs (K_a = 22026 M⁻¹, K_d = 0.045 × 10⁻³ M, ΔG = −24.79 kJ mol⁻¹) were obtained with a reactivity ratio of 1/16/170 (LED/LED@CS NPs/LED-PLA@CS NPs). This indicates that encapsulation enhanced the interaction between the DNA and the LED-loaded nanoparticle systems, without changing the mechanism, and formed thermodynamically stable complexes. The drug release kinetics were assessed under tumor-mimetic conditions (pH 5.5, 10 mM GSH) and physiological settings (pH 7.4, 2 μM GSH). The LED@CS NPs and LED-PLA@CS NPs exhibited drug release rates of 88.0% and 73%, respectively, under dual stimuli over 50 h, exceeding the release rates observed under physiological conditions, which were 58% and 54%, thereby indicating that the LED@CS NPs and LED-PLA@CS NPs systems specifically target malignant tissue. Release regulated by Fickian diffusion facilitates tumor-specific payload delivery. Although encapsulation did not enhance the immediate cytotoxicity compared to free LED, as demonstrated by an in vitro cytotoxicity in HepG2 cancer cell lines, it significantly enhanced the therapeutic index (2.1-fold for LED-PLA@CS NPs) by protecting non-cancerous cells. Additionally, the nanoparticles demonstrated broad-spectrum antibacterial effects, suggesting efficacy in the prevention of chemotherapy-related infections. The dual-responsive LED-PLA@CS NPs allowed controlled tumor-targeted LED delivery with better selectivity and lower off-target toxicity, making LED-PLA@CS NPs interesting candidates for repurposing HCV treatments into safer cancer nanomedicines. Furthermore, this thorough analysis offers useful reference information for comprehending the interaction between drugs and DNA. Full article

Background/Objectives: Glioblastoma represents a particularly aggressive and fatal type of brain tumor. Peptide-drug conjugates, which offer the promise of traversing the blood-brain barrier to selectively accumulate in tumor tissues and precisely target cancer cells, are an active area of research. We present the synthesis and characterization of the T7 peptide (HAIYPRH) as a targeting ligand for the transferrin receptor, which is highly expressed on both the blood-brain barrier and glioma cells. Methods: Using the T7 peptide, the synthesis, characterization, and biological evaluation of a transferrin receptor-targeted, combination SN-38 and rucaparib peptide drug conjugate (T7-SN-38-rucaparib) are described. Results: The T7 peptide drug conjugate readily cleaved in the presence of exogenous cathepsin B, releasing the active drug payloads. In vitro experiments demonstrated potent cytotoxic effects of the T7 peptide drug conjugate on glioblastoma cells (IC₅₀ = 22.27 nM), with reduced toxicity to non-cancerous HEK 293 cells (IC₅₀ = 115.78 nM), indicating selective toxicity toward cancer cells. Further investigations revealed that blocking transferrin receptors with drug-free T7 peptide significantly reduced the conjugate’s cytotoxicity, an effect that could be reversed by introducing exogenous cathepsin B to the cells. Conclusions: These findings highlight the potential of glioblastoma-targeted delivery of SN-38 and rucaparib based on specific recognition of the transferrin receptor for transport across the blood-brain barrier, offering the prospect of reduced toxicity and selective killing of cancer cells. Additionally, since rucaparib does not cross the blood-brain barrier, this work is significant to facilitate the use of rucaparib for the treatment of brain tumors. Full article

Cyanobacteria-derived peptides represent a promising class of anticancer agents due to their structural diversity and potent bioactivity. They exert cytotoxic effects through mechanisms including microtubule disruption, histone deacetylase inhibition, and apoptosis induction. Several peptides—most notably the dolastatin-derived auristatins—have achieved clinical success as cytotoxic payloads in antibody–drug conjugates (ADCs). However, challenges such as limited tumor selectivity, systemic toxicity, and production scalability remain barriers to broader application. Recent advances in targeted delivery technologies, combination therapy strategies, synthetic biology, and genome mining offer promising solutions. Emerging data from preclinical and clinical studies highlight their therapeutic potential, particularly in treatment-resistant cancers. In this review, we (i) summarize key cyanobacterial peptides and their molecular mechanisms of action, (ii) examine progress toward clinical translation, and (iii) explore biotechnological approaches enabling sustainable production and structural diversification. We also discuss future directions for enhancing specificity and the therapeutic index to fully exploit the potential of these marine-derived peptides in oncology. Full article

Background/Objectives: ADCs bring an innovative strategy to cancer treatment by conjugating powerful cytotoxic agents to the specificity of monoclonal antibodies. This review discusses recent advancements and challenges in the field of ADCs, along with future potential applications. Methods: Studies focused on the development of ADCs were reviewed. These include the effects of payload improvements, linker technologies, antibody engineering, and ADC internalization, which were particular topics of examination regarding their role in pancreatic ductal adenocarcinoma (PDAC) and triple-negative breast cancer (TNBC). The efficacy of some ADCs for pancreatic and breast cancers was compared. Results: In TNBC, ADCs such as sacituzumab govitecan and trastuzumab deruxtecan have improved progression-free survival in advanced cases. In contrast, PDAC ADC development is challenged by low antigen density and poor internalization; despite evidence of target engagement in early trials targeting mesothelin and MUC1, ADCs for PDAC have yet to achieve significant clinical efficacy or regulatory approval. Conclusions: While ADCs have significantly advanced treatment options in TNBC, PDAC remains a difficult target due to its stroma-rich microenvironment and lack of high-density, tumor-specific antigens. This article emphasizes the need for tailor-made ADC designs to enhance results in various types of cancers and provides valuable insight into future advancements in precision oncology. Full article

Antibody–drug conjugates (ADCs) are promising cancer therapeutics, but optimizing their cytotoxic payloads remains challenging. We present DumplingGNN, a novel hybrid Graph Neural Network architecture for predicting ADC payload activity and toxicity. Integrating MPNN, GAT, and GraphSAGE layers, DumplingGNN captures multi-scale molecular features using both 2D and 3D structural information. Evaluated on a comprehensive ADC payload dataset and MoleculeNet benchmarks, DumplingGNN achieves state-of-the-art performance, including BBBP (96.4% ROC-AUC), ToxCast (78.2% ROC-AUC), and PCBA (88.87% ROC-AUC). On our specialized ADC payload dataset, it demonstrates 91.48% accuracy, 95.08% sensitivity, and 97.54% specificity. Ablation studies confirm the hybrid architecture’s synergy and the importance of 3D information. The model’s interpretability provides insights into structure–activity relationships. DumplingGNN’s robust toxicity prediction capabilities make it valuable for early safety evaluation and biomedical regulation. As a research prototype, DumplingGNN is being considered for integration into Omni Medical, an AI-driven drug discovery platform currently under development, demonstrating its potential for future practical applications. This advancement promises to accelerate ADC payload design, particularly for Topoisomerase I inhibitor-based payloads, and improve early-stage drug safety assessment in targeted cancer therapy development. Full article

Monoclonal antibodies (mAbs) have become a cornerstone in the treatment of follicular lymphoma (FL), offering highly specific therapeutic targeting that enhances efficacy while minimizing systemic toxicity. Their mechanisms of action include antibody-dependent cellular cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), and direct apoptotic signaling, effectively mediating malignant B-cell depletion. Anti-CD20 mAbs, such as rituximab and obinutuzumab, have significantly improved progression-free survival (PFS) and overall survival (OS), establishing immunochemotherapy as the standard of care for FL. However, the emergence of treatment resistance, often characterized by CD20 antigen downregulation or immune escape, has prompted the development of next-generation mAbs with enhanced effector functions. Bispecific antibodies (BsAbs), which simultaneously engage CD20-expressing tumor cells and CD3-positive cytotoxic T cells, have emerged as a novel immunotherapeutic strategy, redirecting T-cell activity to eliminate malignant B cells independently of major histocompatibility complex (MHC) antigen presentation. Additionally, antibody–drug conjugates (ADCs) offer a targeted cytotoxic approach by delivering potent chemotherapeutic payloads directly to tumor cells while limiting off-target effects. The integration of mAbs with immune checkpoint inhibitors and immunomodulatory agents is further enhancing treatment outcomes by overcoming immunosuppressive mechanisms within the tumor microenvironment. Despite these advancements, challenges remain, including optimizing the treatment sequence, mitigating immune-related toxicities—particularly cytokine release syndrome (CRS)—and identifying predictive biomarkers to guide patient selection. As the role of monoclonal antibodies continues to expand, their integration into therapeutic regimens is transforming the management of FL, paving the way for chemotherapy-free treatment approaches and long-term disease control. This review provides an updated overview of mAbs therapies for FL, emphasizing the advances brought by BsAbs and ADCs toward more tailored and effective treatments. Full article

Prostate cancer is the most common tumor in men in developed countries and it often responds poorly to conventional treatments. Monoclonal antibody (MoAb) therapy, for this pathology, has grown tremendously in the past decades, exploiting naked and conjugated antibodies to cytotoxic payloads to form antibody drug conjugates (ADCs). Several studies have been carried out conjugating biomolecules against prostate-specific membrane antigen (PSMA), highly expressed in this tumor, to cytotoxic drugs. Nano-based formulations show high potential in targeted drug delivery to enhance the bioavailability of drugs. Our research aimed to evaluate the feasibility of setting up a nanoparticle-based multimodal tool for targeted drug delivery, describing the step-by-step approach and to perform a first screening of these fluorescent PEGylated silica nanoparticles employed in selective cancer cell targeting and killing. These nanoparticles featured a core–shell structure to contemporarily conjugate the antibody and the cytotoxic payload monomethyl auristatin E (MMAE) using a step-by-step approach. We compared the cytotoxic effect of this multimodal nanotool near the antibody-MMAE and free MMAE. We found a lower cytotoxicity effect of the nanoparticle-based construct compared to free drugs, likely because of the preservation of the previously observed receptor-mediated endocytosis. Nanomedicine is confirmed as a powerful alternative to organic drug delivery systems, even if some aspects, such as drug loading efficacy, release, scalable manufacturing and long-term stability, need to be deepened. Full article

Despite decades of research, cancer continues to be a disease of great concern to millions of people around the world. It has been responsible for a total of 609,820 deaths in the U.S. alone in 2023. Over the years, many drugs have been developed to remove or reduce the disease’s impact, all with varying mechanisms of action and side effects. One class of these drugs is small-molecule mitotic inhibitors. These drugs inhibit cancer cell mitosis or self-replication, impeding cell proliferation and eventually leading to cell death. In this paper, small-molecule mitotic inhibitors are discussed and classified through their discovery, underlying chemistry, and mechanism(s) of action. The binding/inhibition of microtubule-related proteins, DNA damage through the inhibition of Checkpoint Kinase 1 protein, and the inhibition of mitotic kinase proteins are discussed in terms of their anticancer activity to provide an overview of a variety of mitotic inhibitors currently commercially available or under investigation, including those in ongoing clinical trial. Clinical trials for anti-mitotic agents are discussed to track research progress, gauge current understanding, and identify possible future prospects. Additionally, antibody–drug conjugates that use mitotic inhibitors as cytotoxic payloads are discussed as possible ways of administering effective anticancer treatments with minimal toxicity. Full article